What is a VLAN?

A VLAN, or Virtual Local Area Network, is a technology that allows a physical network to be segmented into multiple logical networks. This segmentation enhances network management and security by allowing the creation of separate broadcast domains within the same physical infrastructure. Each VLAN operates independently even though they share the same physical network components, which can help reduce congestion, control traffic flow, and improve overall network performance.

By isolating different types of network traffic, VLANs can enhance security as sensitive information can be kept on separate logical networks. This means that even if different departments or groups are using the same physical network cable or switch, they can operate on separate virtual networks, thus limiting access to sensitive resources and reducing the chances of potential breaches.

The other choices do not accurately define a VLAN. For example, while it might seem logical that VLANs could help improve bandwidth indirectly by reducing traffic on the same physical network, they are not primarily designed for increasing bandwidth. Similarly, VLANs are not protocols used for routing traffic, nor are they external servers for managing network security. Their primary function is to allow network administrators to segment and manage network traffic efficiently within a local area network.